Multiplying mechanism for checking dividing computations



March 7, 1944. J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTAT IONS Original Filed March 19, 1941 15 shets -sheet 1 INVENTOR.

A TTORNEY 7' March 7, 1944. J. w. BRYCE 2,343,399

' MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIQNS OriginalFiled March 19, 1941 15 Sheets-Sheet 2 IN R. W14 2,, Y

A TTORNEY March 7, 1944. J. w. BRYCE 2,343,399

YMULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 5 INVENTEE ATTRNEY FlG.2a

' March 7, 1944. I .1. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 4 INVENTOR ATTORNEY FIG.2 b

March 7, 1944 J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 5 lNvfgm :6 W i ATTORNEY F'lG.2c

March 7,1944. I J. w. BR YCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed Ma rch 19, 1941 15 Sheets-Sheet 6 imiiiii 2212 22mm N U Q INVENTOR w r N o M w y w 151 L. ATTORNEY J. W. BRYCE March 7, 1944.

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19,

1941 15 Sheets-Sheet 7 wwk ATTORN EY Q T i INVENTOR NOE J. W. BRYCE March 7, 1944.

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 8 mo-wm+mw -wh (if Q.

lNVENTOR ATTORNEY vMarch 7, 1944. J w BRYCE MULTIPLYING MECHANISM FOR CHECKIING DIVIDING' GOMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 9 W N w h-NkN-n A'IITTORNEY March 7, 1944.

J. W. BRYCE MULTIPLYING MECHANISM vFOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, I941 15 Sheets-Sheet 10 INVENTOR W BY ATTORNEY FAY March 7, 1944. J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 11 VdE INVENTOR W I W ATiTORNEY March 1944- J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR C'I IECKING DIVIDING COMPUTATIONS Original Filed March 1 9, 1941 15 Sheets-Sheet 12 00o OGOQKZ'O 000630090 000 2 'o-ooo 62 0000009 90 o ooF'o o o om O oo o OOOGOOOOOOOOOOOOOOOO 309 MC MP ooeofig ho oo oo 0 0 0 o o o O O O 500 00 00 5 0%0 o o o c 'o$o'ooo oooo 0 0 o 0' o o o o 6 o o 6- o 0 5 025 M o o 0 5 2 0 O 36 372 ag 389 Q 0 INVENTOR March 7, 1944.

J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR QHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15 Sheets-Sheet 14 DIV/DING 1 0490 0490 0490 0490 0490 0900 0900 0900 0900 0900 0900 2940 2940 111111-21 MLRB-G 10104-0 0110-5 [EB IE] P0 0490 1410 1960 2450 3430 4410 064000 0900 2940 3920 p R cu y 3 HM [El RD 004000 CUMPHI?! 1 100000 509 100000 314000 t'fl/VPHIYE 1 10000 6569 110000 031000 Raw-000 03100000 MUlT/PlYl/VG r0 (l/[CK /wpl/m D g 06 M6 Rgm 0 11:00 000864 00001100000 00003100000 040 [25:31 Es-As 5P ML1-2 [We-6h 1414-0 m-s in 000004 0011 001 1 0011 0011 0011 049 4 WNW-B 0110-5 MLR-7 {Mm-9| 1 0011 0051 0 060 0005 0119 0153 i 0034 0102 0136 1 11 :1 l1 1! H 1 1 1, 0 J --1' 000031- R'Mfi/NDf/P O 00000o=4x11x10=4x-0 0011/20 0153 0111101 9x010 000600 000104 000I84-F170MR9 INVENTOR A.TTORNEY March 7, 1944. J. w. BRYCE 2,343,399

MULTIPLYING MECHANISM FOR CHECKING DIVIDING COMPUTATIONS Original Filed March 19, 1941 15' Sheets-Sheet 15 ENE Q E QNQ 5% INVENTOR NEE A TTORNEY Patented Mar. 7, 1944 I MULTIPLYING MECHANISM FOR DIVIDING COMPUTATION CgECKING James W. Bryce, Glen Ridge. N. 1., assimor to International Business Machines Corporation, New York, N. Y., a corporation of New York Original application March 19, 1941, Serial No.

384,157, now Patent No. 2,315,688, dated April 6, 1943. Divided and this application September 14, 1942, Serial No. 458,206

2 Claims.

This invention relates to improvements in a record controlled machine, particularly the type which are adapted to periorm either multiplying or dividing computations. The present improvements relate particularly to improvements in multiplying mechanisms for checkin the results of a dividing computation.

This application is a division of application Serial No. 384,157, filed March 19, 19%1, now Patent No. 2,315,686, dated April 6, i943, and claims herein are restricted to the feature of checking the results of a previous dividing com pulsation by a multiplying computation.

In accounting departments of some mercantile establishments multiplying computations are ordinarily desired but occasionally there is the necessity of carrying out an accounting procedure which involves dividing operations. There have been designed heretofore, and used commercially, multiplying machines which are com trolled by records to carry out multiplying computations. devised for carrying out record controlled dividing computations by the use of a separate dividving machine, The provision of a single machine whereby either dividing or multiplying operations may be carried out has heretoi'ore been contemplated and by the utilization of certain apparatus which may be commonly used for both computations a desired simplification in the construction and operation of the machine may be secured. One embodiment oi a machine of this type is fully shown and described in the application of J. W. Bryce et al., Serial No. 213,044, filed June 10, 1938.

Many users of record controlled computing machines insist that for certain classes of work the results of computations be checked and verified for accuracy. It is obvious, of course, that the accuracy of the results of a dividing operation may be effected by a recomputation of the same data. However, when this recomputation is performed by the same dividing mechanism, in the event that an error in the result is obtained by a faulty mechanism, the same error would be likely to occur in the recomputation. The checking operation is therefore not quickly recognized as also being an error and the present invention is primarily directed to improvements in multiplying checking mechanisms whereby the faulty or misoperation of one device would not be likely to occur in checking operations.

It is known mathematically that the factors and results of a dividing operation may be Dividing machines have also beenchecked by going through a multiplying operation. The present improvements in checkin mechanisms are based upon such known mathematics and since in checking operations some of the mechanisms not heretofore utilized for the primary computation areutilized, errors in checking are less likely to occur.

Accordingly, the present invention has {or its main object the provision of a multiplying checking mechanism whereby the iactors'and quotient result and possible remainder of a dividing computation may be checked as to its mathematical relationship by the utilization of such values to control a multiplying operation.

it still further object 0! the present invention is to provide a very simple means whereby, by a single adjustment in the machine, the machine may be conditioned ior checking a dividing computation by carrying out a multiplying computation.

When the machine is conditioned for th primary computation, that is, dividing, the machine performs such computation automatically in the same manner as the machine in the above mentioned Bryce application, Serial No. 213,044. After performing the multiplying checking computation, testing operations in the present machine then automatically ensue and upon 10- cating an incorrectly computed record, a signal is given to the operator so that such records may' be localized, thus enabling the errors to be ascertained by the operator.

A still further object of the present invention is to provide for the operation of thetestin mechanism which determines whether the previous result is correct in such a manner that it will not increase the cycles of operation of the machine so that upon the completion of a multiplying computation carried out for checking previous results, the accuracy of such results .will be obtained with no loss in time and with no extra machine cycles required for checking purposes.

As premised hereinbefore, dividing computations are preferably checked by multiplying the quotient and divisor factors and comparing the sum of the computed product and remainder result against the dividend. This object of the invention is carried out by the adoption of a simple testing mechanism by means of which the checking oi the computation can be directly obtained immediately upon the completion of the multiplying computation. Preferably in carrying out checking of the factors and result of dividing computations by multiplication, the

if the multiplying operation was correctly carried out.

The dividing machine shown herein and also in the Bryce application, Serial No. 213,044 above referred to is capable of taking into consideration the decimal point of the factors of division and accordingly the quotient and remainder result will be indicated-on the record card with regard to the decimal point. In carrying outthe checking of division by multiplying computations, the various values involved are denominationally entered in the accumulators with regard to their decimal point. This is necessary because the remainder might either be a whole number or a decimal and its entry in the checking accumulator must accordingly be shifted and entered in the proper denominational positions. This is also true of the dividend result which is entered in the checking accumulator as well as the quotient result which is preferably utilized as the mul- .tiplicand and in which multiples thereof are built up as a prerequisite to multiplying computations.

While the aforementioned checking mechanism has been shown in connection with the composite multiplying and dividing machine shown inethe aforementional Bryce application, Serial No. 213944.211; is to be understood that such incorporation is merely illustrative and not restrictive. It is to be further understood that the present showings are merely the preferred embodiments of the invention and by obvious modifications the same objects may be carried out without, however,

. departing from the spirit of the invention.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings,'which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 and Fig. 1a taken together with Fig. 1a to the right of Fig. 1 show a somewhat diagrammatic view of the various units of the machine and the drive therefor.

Figs. 2a to 2h inclusive taken together show the complete circuit diagram of the machine when arranged as shown in Fig. 3.

Fig. 3 shows the manner in which Figs. 2a to 2k should be coordinated.

Fig. 4 is a cam timing diagram showing the timing of the various CC contacts.

Fig. 5 is a cam timing diagram of the FC cams.

Fig. 6 is a cam timing diagram of the KC cams.

Fig. 7 shows the plugging of the insertible plug-board for effecting a simple multiplying calculation.

Fig. 8 shows the plugging of the insertible plugboard for a dividing calculation.

Fig. 9 is a flow diagram of a typical dividing computation as'performed by the machines.

Fig. 10 shows the flow diagram of the computation performed by the machine'when a multiplying computation is carried out to check the results of a previous dividing computation.

Fig. 11 is aiiowdiagramofatypicalmultiplying computation as performed by the Inlchine.

The above Figs. 9, 10 and 11 are illustrative problems and show the manner of eflccting entry into the various receiving devices and how the machine performs different typical computation. Each diagram is accompanied by a designating legend giving the particular calculation which is illustrated in the diagram.

Fig. 12 is a sequence of operation diagram which shows the successive cycles of operation effected when a multiplying computation is utilized to check the results of a previous division computation.

Fig. ,13 shows the plug ng of the inser ible plugboard when the multiplying mechanism is utilized to check the results of a dividing computation.

Machine drive Referring first to Figs. 1 and 1a, in general the machine comprises six accumu ating units which are respectively designated SP, 'Q, RD. ML, MP, and PQ. It may be explained that the unit ML contains accumulators and readouts from which all of the nine digital multiples of the divisor or multiplicand can be derived depending upon whether the machine is used for division or multiplication. The MP receiving device receives the multiplier upon entry in the multiplying calculations. Such unit is not utilized in dividing. The accumulating units LQ and RD receive components of the products upon multiplication with the final product formed in IQ and upon division LQ receives the quotient amount and RD the dividend amount. When checking these calculations the PQ accumulator replaces the LQ in the above mentioned operations. The SP unit is utilized on checking computations. The various ac cumulating units are driven by the gearing delineated from the driving motor M. The machine is also provided with a direct current generator DC. The card handling and feeding section of the machine is of customary form like that shown in Daly Patent No. 2,045,437 and is driven in the usual manner. The FC cam contacts (ML-l6, Fig. 1a) are also driven in the customary' manner in synchronism with the drive of the card handling section of the machine. The units designated CY, NR, and TT are electromechanical relay setup units of the general construction shown in Figs. 16 and 17 of Patent No. 2,315,686. Each of these units is adapted for reset from the constantly running drive shaft by the customary one revolution clutch arrangement. The reset magnets for the units are respectiveh designated 32ICY, 32|NR and 3ZI'I'I'. The comparing units are as shown diagrammatically at CUCU. These comparing units are of the forms shown in Figs. 12 to 15 inclusive of the Patent No. 2,315,686 and such units are adapted to be driven from the drive shaft by the use of the well known onerevolution clutch, the clutch magnet being designated 342. Also driven from the main drive shaft are the usual 00 cams dmignated CCill and the impulse distributor SIG. In addition there are also provided eight impulse emitters which are designated 3, 3, 322, ill, 5! I, 315, I, and 350. Referring now to the XCl-ll cam contacts, such cam contacts are driven from the drive shaitthrough a one-revolution clutch which is controlled by magnet ill. The drive side of the one-revolution clutch receives its drive from the main drive shaft through the gearing shown ans-races which drives the X cams one revolution for each Accumulators and entry receiving devices As stated, the SP, LQ, RD, ML and MP units are accumulators of electromechanical type. These accumulators are identical in construction except for the number of readout sections, some accumulators having four readout sections and others having two. The accumulator which is here employed may be of various types known in the art, more particularly the type of accumulator having electrical transfer and eilectrical reset. Suitable accumulators of this type are shown and described in United States Patent No. 1,834,767. and suitable readout structure may be that shown in United States Patent No. 2,062,117 employing the electric reset of Patent No. 1,834,767, modified as per British Patent No. 422,135. v

The present invention involves transfer total arrangements according to British Patent No. 422,135. 3

While the aforesaid accumulators are of suitable type for use with the present invention, preferably a preferred accumulator is of the form illustrated and described in the Lake and Pfaii Patent No. 2,232,006, dated February 18, 1941, and more fully shown inthe parent Patent No. 2,315,686.

Insertible plugboards In order to quickly shift the machine controls from one status in which it is capable of effecting one type of computation to another status for effecting another type of computation use is made of insertible plugboard elements. This insertible plugboardconstruction is of a type known in the art and the insertible plug unit is generally indicated at Ill in Fig. 18 of Patent No. 2,315,686. Devices of this type are generally known as automatic plugboards" and a suitable form of such board is shown and fully described in the patent to C. D. Lake, No. 2,111,118. Such automatic piugboard arrangement comprises a series of relative fixed machine sockets to which the fixed machine wiring is connected. Adapted for cooperation with such sockets are plug prongs carried by a replaceable plugboard assembly or unit.

Such plug prongs 0n the replaceable board are in turn connected to plug sockets upon the replaceable board. These plugboard sockets may be in turn. plugged up by the operator selectively at will or the entire board may be pre-plugged with a desired set of connections.

The manner in which the replaceable plugboard units Hi are wired and plugged for different computations is shown in Figs. '7, 8 and 13.

It may be explained that the plug socket reference numerals used on the circuit diagram will have similar reference numerals to those used on the diagrammatic plugboard views.

Cam timing diagrams tion of Bryce et al., Serial No. 213,044 have the same timing. Cams which have designating numbers higher than any of the numbers used in the application referred to are extra cam contacts utilized for the operation of certain mechanisms not disclosed in the application referred to.

Multiplying It will be assumed that a set oi record cards are in place in the supply magazine of the machine and the machine is plugged according to Fig. 7. The operator then closes line switch 300 (Fig. 271). Closure of line switch 300 starts the main drive motor M into operation. Coupled to the main drive motor M is a direct current generator DC which supplies current to the line 31". The operator now depresses start key 302 (Fig. 2d) and a circuit is completed from ground through FC3 contacts, through the FI contact through the start key 302, through relay coil E to line 30L The relay coil E being energized is maintained energized by a stick circuit through relay contacts El and cam contacts FC2. The energization of relay coil E closes relay contacts E2 and a circuit is completed from ground through C029, through PI, through E2, through JJ2, through stop key contact 303, through the card feed clutch magnet 304, through Di to line 30!. The card is now fed by the card feeding and handling section of the machine and is advanced towards the reading brushes in the usual way. In starting up the machine on the run of cards the start key must be maintained depressed for two card feed cycles or it may be depressed and released and redepressed. The cyclic sequence for multiplying is shown in Fig. 28 of the parent Patent No. 2,315,686.

Late in the second machine cycle of the card feed cycle, the card lever contacts 305 -(bottom of Fig. 2d) close, bringing about an energizationv be supplied to the impulse distributor 306 from which current impulses flow to the card transfer and contact roll 30?. The usual regular reading brushes 303 are provided which are connected to plug hubs generally designated 309. The energiz ation of relay coil G also causes the relay contacts G6 to become be established not only to the card feed clutch magnet 304 (Fig. 2d) in a manner previously traced but a branch circuit will be established through the G4 contacts, through the clutch magnet 312 to line 30L releases for rotation the group of XC cams (see also Fig. 1) which upon release function for three machine cycles. During this second cardfeed cycle relay coil G causes closure of relay contacts G2 (Fig. 2c). The current flows from ground through the now closed G2 contacts through cam contacts FCi I over through contacts Rhl, through relay coil Th, to line 30!. The energization of coil Th causes closure of the group of contacts Th2--3 (Fig. 2a). These contacts remain closed during the entry portion of the feed cycle. Also during the entry portionoi this cycle, cam contacts XCI close to energize relay coil K (Fig. 201). With relay coil K energized, the Kl-l2 contacts (Fig. 2a) are closed. The MC amount is then entered into the ML accumulator through the Tn2-4 contacts now in closed position down to the now closed Kl-i2 contacts. By the plug connection between plug hubs 303 to 311 the closed and a circuit will This clutch magnet amount of this multiplicand is entered through contacts lid-4 into the following multiple receiving devices MLi--2 MLl-i, MLI, ML! and At this point it may be explained that the multiple receiving devices are commonly used for both .a 820111.) of lines generally designated iii (Figs. .2a, D).

From these lines at Fig. 2b the impulses flow through the Li-l8 contacts (Fig. 2a) which are now closed and ultimatelyq-eachthe MLJ-i,

multiplying operations and for dividing operations. In multiplication these multiple receiving devices are used to build up and store nine difierent multiples of the multiplicand and on division the same multiple receiving devices are used to store nine diilerent multiples of the divisor. The multiple receiving devices have been previously described. These are inthe form of electrically controlled accumulators with electrical readouts. The MLi-Z, the ML3--6 and the MIA-8 receiving devices .are provided with doubling readouts in addition to the usual straight readouts. The other multiple receiving devices are provided with straight readouts only. On the entry portion of the feed cycle as explained, the amount of the multiplicand is entered into five of the multiple receiving devices concurrently.

The multiplier is entered into the MP accumulator in the following manner: Through the plug sockets 3M (Fig. 2e), through the MPl-3 contacts, now-in the position shown, to the 3i3MP accumulator magnets to ground. The amount of the multiplier is thus entered into the multiplier receiving devices. coincidentally with this setup of the multiplier in the multiplier receiving device, there is a setup of the cycle controller and this setup is made according to the significant digits in the multiplier amount. Assuming ill to be the amount of the multiplier, at the "7" index point in the cycle, the A1311 (Fig. 2e) relay coil is energized, at the 4 index point the A'Dt relay coil is energized, and at the 1 index point the ADh relay coil is energized. During the entry cycle controls are set up to cut oh" the start key control circuit and to also maintain operation of the machine under record card control. Referring now to Fig. 2d, early in the entry cycle cam contacts FCI close, energizing relay coil F.

F being energized, it is'rnaintained energized by a stick circuit which is'completed through contacts Fl and cam contacts FC3. The shift of the Fl contacts cuts oil the circuit to the start key contacts 392; Energization of F closes contacts F2 to maintain a stick circuit for relay coils F and G either through F03 or the card lever contacts 3".

Building up of multiples It has been previously explained that on the entry cycle, the multiplicand amount was entered into Mill-2, MLl-G, ML5, ML'I and MLB. In the machine cycle following the entry cycle there occurs the first step in the build up of further multiples. As stated, the limb-2 device is provided with a doubling .readout. This is designated MLl-2 on Fig. 2b. In this machine cycle can contacts X62 (Fig. 2d) close, energizing relay coil L. With relay coil L energized, relay contacts Ll.l6 (Fig. 20) close and current supply is afforded through the adding emitter 3 (Fig. 2b) as follows: From line-3M through the contacts MMi now closed, through th contacts ML", also closed, through emitter ill, then the impulses flow over to the transverse busses of the doubling "section of-MLRi-Z down through the piloting section of this readout and out via and D2 ML! and ML! accumulators or multiple receiving devices. This operation will have completed the build-up of the three multiple in On the following machine cycle cam contacts XC3 (Fig. 2d) close, energizing relay coil M and causing closure 01' contacts Mi-l8 (Fig. 2a). With the emitter 3 in operation the two multiple of the multiplicand is read out from the MI..R.I2 and flows via lines M5 and through the Ml-8 contacts to the MIA-8 and the ML! accumulators. This will have completed the building up of the tour and the live multiples in these receiving devices. During the same cycle in which these entries are being made, the six multiple of the multiplicand is read out from the doubling readout section of MLR36 and such six multiple flows via lines 3i5, through the MS-IB contacts and finally reaches the ML! and the MLB receiving devices, This operation will have completed building up of the nine multiple in ML9 and the seven multiple in MLl. The multiple building up operations are now completed.

During the second card feed cycle the record card from which the factors were read is advanced to the punch tray in the usual manner. Upon reaching this tray, the contacts 3!! close (Fig. 2d, right) to energize relay coil D. Energizing of relay coil D shifts relay contacts DI (Fig. 2d, left) to a. reversed position from that shown cutting off current supply from the card feed clutch magnet 30! and providing current supply for the punch rack trip magnet 3l8, upon closure of cam contacts CCI, with contacts P3 and the relay contacts Bl closed. The relay contacts Bl become closed by the energizatlon of relay coil B (Fig. 2d, right), upon closure of the customary last column punch contacts P5. With the punch rack trip magnet 318 energized, contacts 3I9 (Fig. 2h) becomes closed and remains latched closed in the customary manner by latch 320 (Fig. 2h). Current supply is then provided for the punch driving motor PM, and endwise card feed occurs in the usual way to feed the card to the first product punching posi-- tion.

Reset With the relay coils B and D energized in the manner previously explained, relay contact B2 of cam contacts CCZ'I current will flow from the line 30l through these contacts through the relay contacts HH2, through the relay contacts AG3. through the relay contacts AK, through 32|LQ to ground. Reset oi the Q accumulator will then be efiected. The present machine employs electric reset and provision is accordingly made to maintain the 32ILQ relay coil energized during the reset cycle. This is provided for by means of stick contacts LQI I, such contacts being in a stick circuit including cam contacts CC5. Upon en'ergization or the 32ILQ relay, contacts LQI6 (Fig. 2c) and contacts LQl are now closed; thus supplying current from line 30! through LQl to the emitter 322. 'The emitter 322 is wired complementary to the LQ readouts. Complemental impulses representative of the nines complement 01' the amount standing in LQ now through the now closed LQl-t contacts (Fig. 2e) become closed. Upon closure ascasae through the set of lines generally designated 323 (see also Fig. 2g), through the At 3-8 contacts down to the tilZiLQ accumulator magnets to ground (Fig. 29). By thus introducing the nines complement of the amount standing in LQ the accumulator elements are restored to a "9" position. To bring the accumulator to zero from the all "9" position, an elusive one is entered in units order at the carry time in the cycle. This entry is provided through the contacts LQlll (Fig. 29) which are closed in the manner previously explained. This impulse is supplied in the following manner: From line tlfll, through cam contacts CCES, via line 323 through the LQ! a contact, through the normal carry relay contacts Av lc controlled by the relay coil AV down to the units order of the SIIELQ magnets. The units order is thus advanced one step and the electric transfer devices of the accumulator cause advance of all the other higher orders one step.

It may be explained that as long as the machine is operating cam contacts CO2 (Fig. 2d, right) close once each machine cycle at the carry time in the operation of the accumulators. Such closure of cam contacts CO2 energize relay coil AV. The energization of the coil AV closes all of the associated AV contacts. Since coil AV becomes energized once each machine cycle, the aforementioned relay contacts thus close at the carry time. The closure of these contacts permits the electric carry devices to be effective for performing carry operations whenever they are required in their related accumulators.

During LQ reset provision is made to prevent repetition of such reset. This reset preventing means is provided for as follows: During LQ reset the LQQ (Fig. 2d, right) contacts are closed. Accordingly, when cam contacts C06 close, a circuit is provided from ground through the A112 contacts through LQQ, through (306, through Mild, through i-IH relay coil to line 3M. Relay coil HH becoming energized establishes its stick circuit through contacts l-IHI! and the punch control contacts P2 now closed. The relay contacts EH2 open and thus interrupt the reset initiating circuit to 326% (Fig. 2e)

Computing operations-of the machine, that is to say the adding of selected multiples of the multiplicand into the product receiving device, are initiated by LQ reset. From the LQQ contacts a branch circuit extends to contacts CC'l, H5, through the JJ relay coilto line to! to energize the JJ relay upon closure of cam contacts CCl. JJ relay once being energized is maintained energized by a stick circuit through JJ l contacts, M129 contacts back to ground. The ML contacts open earlier than is desirable so CClB contacts in shunt with M1129 maintain the stick circuit for the required length of time. Coil JJ is the computing initiating control relay.

In general, the machine has two cycle controllers. One cycle controller derives its control from odd number columns of the multiplier. The other cycle controller derives its control from even number columns of the multiplier. Each cycle controller tries to cause its operation in the minimum number of successive machine cycles and both cycle controllers can operate concurrently. One cycle controller will direct entries into one accumulator and the other cycle controller will direct entry into the other accumu lator. In the complete wiring diagram only a three order multiplier is utilized but in practice this multiplier might contain many more orders.

The cycle controller, however, is shown with provision ior more than three orders, in order that its principles of operation may be disclosed and understood. The general function of this cycle controller is described in greater detail in the Bryce et al. application, Serial No. 213,044.

Upon energization of relay coil JJ in the manner previously explained, relay contacts JJ4 (Fig. 2]) are closed and upon closure of cam contacts CC28 a circuit is completed as follows: From line 3!" to'AKQ through C028 cam contacts, through MLTI, through JJd, through MGSA to ground. thus energizing the stepping relay magnet- SlflSA. Upon energization of 3408A the stepping switch arms 01 the cycle controller are advanced from normal contact position to the first contact position (Fig. 2e). In Fig. 2e, the first contact position of switch SA is that which is in circuit with contacts ADM-5, ADul5. The energizatipn of relay coil JJ will have closed contacts JJ5 (Fig. 2e) and upon closure of cam contacts C03 and C028 current will flow from line 30!, through (263, through J35, through the ADuE contact now in closed position as brought about by the energization of the AD magnet in the manner previously explained, down through wire 326, through the coil CSa of the column shift relay and back to ground. A circuit is also completed through contacts ADti through lines 321 to the column shift relay magnet CSc back to ground.

The energization of CS4 will close its related column shift contacts shown in Fig. 2c and direct the entry of the multiple related to the units order oi the multiplier into the proper columns of the RD result accumulator. The energizatlon of CSc will close its related column shift contacts on Fig. 2c and direct the entry of the multiple pertaining to the tens order of the multiplier and the LQ. Concurrently with the energizing of the above mentioned shift magnets CS: and CS0, current supply is afi'orded through lines 326' and 3st to the units and tens common segments of MR (Fig. 2f) With the problem under consideration (see Fig. ll) the multiplier amount is Ml so the brush in the units order of MR will stand at seven. and the brush in the tens order will stand at four. With the brushes in these positions, the brush in the units order will allow current to how to the RX multiple selecting tolay. The circuit bacls to ground is through AKB relay contacts now closed. The brush in the tens order will permit energization of the iXX multiple selecting relay. The respective multiple selecting relays X and m have stick contacts such as lxi and fiXXl which, when closed, establish stick circuits which not only maintain their related multiple selecting relays energized but also maintain the selected column shift relays energized. The stick circuit for the XX relay is via line etc which extends back to line 38! through line '33! and cam contacts CCI5. The stick circuit for the X relays is via line 31 which extends to line 3M, through the cam contacts CCIB.

With the above mentioned multiple selecting relays energized, the related contacts such as dXXZ-S and 'lX2-5 (Fig. 2b) will become closed. and a readout of the four multiple will be permitted from the readout section of MIRA-4, with the entry or such four multiple into LQ. The path of impulse flow from the contacts 4XX2-5 is 'via a group of lines generally designated 332 (Figs. 211-21) which extend to contacts AK! 8-! 9 (Fig. 2a) in the position shown and the impulses will flow through these contacts throughthe 

